add version A information

README.md

@@ -63,3 +63,13 @@ version
 0:
 working version
 
+A:
+first prototype built using CircuitPro + ProtoMat S63
+bugs:
+- the hole for the USB and header pins are too wide. I hope it would create some through hole plating thanks to capillarity, but it didn't
+- wider vias annulus would be a good idea
+- DTR it set (to low) when the serial port is opened, but is no reset (to high) when closed (FT4232H specific)
+- RTS can be reset to high on close, but that need to be programmed in the FT4232H's EEPROM
+- the 3.3 V on DTR can not drive the pMOS because it's switching 5.0 V, but V_GS < 1.1 V
+- decoupling capacitors on the serial lines should improve the quality
+- try if with less feritte beads and decoupling capacaitors PLL still works